diff --git a/pymongo/__init__.py b/pymongo/__init__.py
index a30c74ecf..b72bcc3ce 100644
--- a/pymongo/__init__.py
+++ b/pymongo/__init__.py
@@ -77,7 +77,7 @@ SLOW_ONLY = 1
 ALL = 2
 """Profile all operations."""
 
-version_tuple = (2, 9)
+version_tuple = (2, 9, 1, '.dev0')
 
 def get_version_string():
     if isinstance(version_tuple[-1], basestring):
diff --git a/setup.py b/setup.py
index dc4a79ede..0f591a29a 100755
--- a/setup.py
+++ b/setup.py
@@ -33,7 +33,7 @@ from distutils.errors import CCompilerError
 from distutils.errors import DistutilsPlatformError, DistutilsExecError
 from distutils.core import Extension
 
-version = "2.9"
+version = "2.9.1.dev0"
 
 f = open("README.rst")
 try: